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51.
ObjectiveThe objective of this study is to assess the utility of a nucleic acid amplification test‐based approach to shorten isolation of healthcare workers (HCWs) with COVID‐19 in the setting of the highly transmissible omicron variant.MethodsBetween December 24, 2021, and January 5, 2022, HCWs who tested positive for SARS‐CoV‐2 were retested with PCR at least 5 days since onset of symptoms.ResultsForty‐six sequential fully COVID‐19 vaccinated HCWs who had tested positive for SARS‐CoV‐2 underwent follow‐up testing. All the samples were confirmed as omicron variants and only four (8.7%) were negative in the follow‐up test performed at a median of 6 (range 5–12) since onset of symptoms.ConclusionsImplementation of a test‐based strategy is logistically challenging, increases costs, and did not lead to shorter isolation in our institution.  相似文献   
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The general objective of this article is to show the relationship that exists in the COVID-19 pandemic, the mental health of people and the propensity for work-related accidents in companies. Various results are shown that detail how COVID-19 has generated and is generating mental alterations in people such as post-traumatic stress disorder, PTSD for its acronym in English. Likewise, data are presented that report the influence of mental health as a precursor to workplace accidents in different industries, with which it can be concluded that COVID-19 needs a comprehensive approach in companies to prevent it from negatively impacting workers and they end up accident during their daily work. Some concrete actions are proposed to promote and avoid in companies so that workers can be better managed in times of a COVID-19 pandemic.  相似文献   
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Tin-bronze alloys with a tin content of at least 10 wt% have excellent mechanical properties, wear resistance, and corrosion resistance. Among these alloys, Cu-10Sn was investigated in this study for production with the laser powder bed fusion process with a 500W Yb:YAG laser. In particular, a design of experiment (DoE) was developed in order to identify the optimal process parameters to obtain full density, low surface roughness, and high dimensional accuracy. Samples were characterized with Archimedes’ method and optical microscopy to determine their final density. It was shown that the first method is fast but not as reliable as the second one. A first mechanical characterization was performed through microhardness tests. Finally, a set of process parameters was identified to produce fully dense samples with low surface roughness and high accuracy. The results showed that the volumetric energy density could represent an approach that is too simplified, therefore limiting the direct correlation with the physical aspects of the process.  相似文献   
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Hypertension (HTN) is one of the main cardiovascular risk factors and is considered a major public health problem. Numerous approaches have been developed to lower blood pressure (BP) in hypertensive patients, most of them involving pharmacological treatments. Within this context, natural bioactive compounds have emerged as a promising alternative to drugs in HTN prevention. This work reviews not only the mechanisms of BP regulation by these antihypertensive compounds, but also their efficacy depending on consumption time. Although a plethora of studies has investigated food-derived compounds, such as phenolic compounds or peptides and their impact on BP, only a few addressed the relevance of time consumption. However, it is known that BP and its main regulatory mechanisms show a 24-h oscillation. Moreover, evidence shows that phenolic compounds can interact with clock genes, which regulate the biological rhythm followed by many physiological processes. Therefore, further research might be carried out to completely elucidate the interactions along the time–nutrition–hypertension axis within the framework of chrononutrition.  相似文献   
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A survey of the presence of aflatoxin M1 (AFM1) was carried out on eight traditional dairies belonging to four sectors of Fez city situated in the northern center of Morocco. Raw milk samples were collected between October 2009 and September 2010, and analyzed by LC-fluorescence detection after immunoaffinity purification. AFM1 was detected in 13 out of 48 samples (27%) at concentrations ranged between 10 and 100 ng/l. Within these positive samples, four (∼8% of the total) were above the European legislation limit of 50 ng/l. This study revealed a variation of contamination from one sector to another with a higher incidence in milk samples collected in autumn compared to those collected in other seasons suggesting a link between feeding practices, such as the use of silage and AFM1 contamination. This is the first report on AFM1 contamination in raw milk directly collected from Moroccan traditional dairies. The levels of contamination found justify more detailed and continuous monitoring to assess the public health implication and reduce consumers’ exposure to AFM1.  相似文献   
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Bile acid sequestrants (BAS) lower plasma low density lipoprotein levels and improve glycemic control. Colestimide, a BAS, has been claimed by computed tomography to reduce liver fat. Therefore, we examined the efficacy of colesevelam, a potent BAS, to decrease liver fat in patients with biopsy-proven nonalcoholic steatohepatitis (NASH). Liver fat was measured by a novel magnetic resonance imaging (MRI) technique, the proton-density-fat-fraction (PDFF), as well as by conventional MR spectroscopy (MRS). Fifty patients with biopsy-proven NASH were randomly assigned to either colesevelam 3.75 g/day orally or placebo for 24 weeks. The primary outcome was change in liver fat as measured by MRI-PDFF in colocalized regions of interest within each of the nine liver segments. Compared with placebo, colesevelam increased liver fat by MRI-PDFF in all nine segments of the liver with a mean difference of 5.6% (P = 0.002). We cross-validated the MRI-PDFF-determined fat content with that assessed by colocalized MRS; the latter showed a mean difference of 4.9% (P = 0.014) in liver fat between the colesevelam and the placebo arms. MRI-PDFF correlated strongly with MRS-determined hepatic fat content (r(2) = 0.96, P < 0.0001). Liver biopsy assessment of steatosis, cellular injury, and lobular inflammation did not detect any effect of treatment. Conclusion: Colesevelam increases liver fat in patients with NASH as assessed by MRI as well as MRS without significant changes seen on histology. Thus, MRI and MRS may be better than histology to detect longitudinal changes in hepatic fat in NASH. Underlying mechanisms and whether the small MR-detected increase in liver fat has clinical consequences is not known. (HEPATOLOGY 2012;56:922-932).  相似文献   
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We report the case of a sacral neurinoma, which presented with mild hydronephrosis, due to compression of the right ureter, in a 71-yr old woman admitted to our hospital with recurrent urinary tract infections. CT and MRI detected a 4 x 4 cm mass pressing on the right ureter at the sacral level, in continuity with the second sacral foramen. Given this finding, the mass was thought to be of presumable neurogenic origin. In order to both reach a conclusive diagnosis and relieve the compression of the ureter, a laparoscopic resection of the mass was performed. Surgery was successful and the pathologic examination revealed a sacral Antoni A neurinoma. Neurinomas, also called Schwannomas, are uncommon benign nerve sheath tumors arising from Schwann cells. Their diagnosis can be extremely difficult due to their aspecific symptoms and the lack of pathognomonic characteristics on imaging exams. Therefore, histopathologic evaluation is essential in establishing the diagnosis. Surgical resection seems to be the best approach, both for diagnostic and therapeutic purposes.  相似文献   
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